Effect of somatostatin on growth hormone and prolactin response to dermorphin in man

The effects of iv somatostatin (somatotrophin release inhibiting factor (SRIF) on growth hormone (GH) and prolactin (Prl) response to dermorphin (D) were tested in 6 healthy men. In all subjects D induced a significant increase in GH and Prl levels, as expected. SRIF completely blocked the GH-releasing activity of D, whereas it only reduced the Prl-releasing activity. The results confirm that D is a potent stimulant for GH and Prl release in man, and furthermore demonstrate that the action of D on GH secretion can be completely overridden by SRIF.